Riverplate handed a walkover to the quarter-finals as rivals Boca Juniors are ousted from the competition for their fans violent actions.

The players were initially suspected of being affected by tear gas but

Buenos Aires, May 17 (IANS): Argentine football team Boca Juniors have been thrown out of the Copa Libertadores tournament after some of the team's fans sprayed an irritant on River Plate players during the second leg of the last 16 tie.

Boca have also been fined $200,000 and have to play four home games behind closed doors and four away without its supporters.

South American Football Confederation handed River Plate a walkover to the quarter-finals of the competition, the continent's premier football competition, where they will face Brazil's Cruzeiro, BBC reported on Sunday.

The last 16 second-leg tie between the two arch-rival team's here was abandoned with the score at 0-0 on Thursday. River were leading the tie on aggregate after winning the first leg match 1-0.

Four River Plate players were taken to a hospital following the half-time incident at Boca's home ground, the La Bombonera stadium.

The attacker is believed to be a suspected hooligan known as "El Panadero", according to media outlets on Saturday, although Argentine authorities have not officially confirmed that.

River Plate players were preparing to take the field through an inflatable tunnel for the start of the second half when a hooded assailant threw the substance at the players, who emerged from the tunnel with teary eyes and irritated skin.

Toxicology tests have revealed that the irritant used to attack was a homemade concoction consisting of hot pepper sauce, cayenne pepper and acid, local media reported on Saturday.

That mixture, which is known as "mostacero" in prison culture and produces skin irritation and a burning sensation, was identified through analysis of wall stains at La Bombonera stadium.

The analysis ruled out an initial hypothesis that the players may have been mistakenly sprayed with pepper gas by police who responded to the disturbances.

The security lapses and unruly crowd behaviour made news worldwide and a group of Boca Juniors fans has sued the club and its chairman Daniel Angelici for "moral damage" and other unspecified harm suffered by spectators as a result of the incidents.